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We welcome the comments by Bjorn Robroek et al. ( The Holocene 19 (2009) 1093—1094, this issue) on our paper (McClymont et al., The Holocene 18 (2008) 991-1002) and the opportunity to discuss further the complexities that surround the disappearance of Sphagnum imbricatum from Butterburn Flow (our study), and the implications for understanding the disappearance of this species in northwest Europe. We also wish to clarify our site of study; we presented data only from Butterburn Flow, northern England. Although we note that the disappearance of S. imbricatum here is part of a wider European decline in the late Holocene, we did not present data from Wales or Ireland as suggested in the opening paragraph of Robroek’s comment. We also noted that the replacement of S. imbricatum by S. magellanicum occurred over c. 44 years, but proposed that it may have been longer owing to evidence for reduced peat accumulation across the transition.

Ice cores from the relatively low-lying ice caps in Svalbard have not been widely exploited in climatic studies owing to uncertainties about the effect of meltwater percolation. However, results from two new Svalbard ice cores, at Lomonosovfonna and Austfonna, have shown that with careful site selection, high-resolution sampling and multiple chemical analyses it is possible to recover ice cores from which part of the annual signals are preserved, despite the considerable meltwater percolation. The new Svalbard ice cores are positioned in different parts of Svalbard and cover the past 800 years. In this paper we focus on the last 400 years. The 6180 signals from the cores are qualitatively similar over most of the twentieth century, suggesting that they record the same atmospheric signal. Prior to AD 1920, the Austfonna ice core exhibits more negative 6180 values than Lomonosovfonna, although there are intermittent decadal-scale periods throughout the record with similar values. We suggest that the differences reflect the effect of the inversion layer during the winter. The pattern in the 6180 records is similar to the Longyearbyen airtemperature record, but on an annual level the correlation is low. The Austfonna record correlates well with the temperature record from the more distant and southwesterly located Jan Mayen. A comparison of the ice-core and sea-ice records from this period suggests that sea-ice extent and Austfonna 6180 are related over the past 400 years. This may reflect the position of the storm tracks and their direct influence on the relatively low-altitude Austfonna. Lomonosovfonna may be less sensitive to such changes and primarily record free atmospheric changes instead of variations in sea-ice extent, the latter is probably a result of its higher elevation.

This paper summarizes Isothermal Remanence (IRM300mT) measurements from Holocene ice-core samples from two contrasting glaciological regimes: (i) the Greenland ice sheet and (ii) a Himalayan glacier. Cores had been previously characterized in terms of chronologies, geochemistry and, for the Himalayan core, microparticle concentrations. Six samples from the Greenland 20-D ice core from the time period AD 1876-1983 did not yield magnetic measurements above instrumental noise-level. Significant Isothermal Remanence measurements (IRM300mT) were obtained from some levels in the Himalayan ice core. Scanning electron microscopy and EDAX analyses indicate weathered crustal material. The techniques used require ice-core samples with relatively high dust loadings and/or larger volume ice samples.